Fundamentals of UML Diagrams
A diagram is the graphical presentation of a set of elements. UML has a lot of different diagrams. Make sure you can differentiate between different diagrams. Previous sections described UML diagrams; this section elaborates on them using examples.
Using the <> relationship
Collaboration Diagram
A collaboration diagram is an interaction diagram that emphasizes the structural organization of the objects that send and receive messages. Collaboration diagrams express both the context of a group of objects and the interaction between these objects.
It focuses upon the relationships between the objects. They are very useful for visualizing the way several objects collaborate to get a job done and for comparing a dynamic model with a static model. When creating collaboration diagrams, patterns
are used to justify relationships. Patterns are best principles for assigning responsibilities to objects. Figure 2.10 shows an example of a collaboration diagram.
Figure 2.10: Example of a Collaboration Diagram
Note for Sequence and Collaboration Diagrams
- Interaction diagrams require use cases, system operation contracts, and domain (class or conceptual) model to already exist
- Sequence diagrams and collaboration diagrams are isomorphic, meaning that you can take one and transform it into the other.
- Collaboration and sequence diagrams describe the same information, and can be transformed into one another without difficulty.
- The choice between the two depends upon what the designer wants to make visually apparent.